I/we will miss it
Started using it for my family in the days before Facebook had private groups.
The 'Circles' concept is a bit of a brain burner because everybody is used to admin managed permission based groups, but is actually brilliant and if it had come first, then I am pretty sure it would be the de facto method of group sharing.
I guess Facebook is now going to be home of family holiday snaps, but OMG how I hate that platform. Am open to suggestions for alternatives!